In order to maintain a uniform spacing between parallel rails of railroad track systems, transverse rail-spacing gauge-plate members are fixedly mounted between the parallel rails. The rails have traditionally been made of a metal such as steel selected for strength, durability, and electrical conductivity, while the rail-spacing members have traditionally been made of a metal such as steel selected for strength and durability but not for electrical conductivity. In addition, railroad tracks are typically divided into sections (or blocks) and each section is electrified to provide for detecting the presence of a train on any given section of the track. The train-detection systems monitor the sections of the track to determine whether the metallic rails are isolated from each other (indicating that no train is present on those track sections) or whether they are short-circuited (by a train providing an electrical path between the rails to indicate that a train is present on that track section).
To electrically insulate the parallel rails from each other, inline pairs of the rail-spacing members are provided with their outer-positioned ends mounted to the rails, their inner-positioned ends spaced apart, and a gauge-plate insulator mounted to their spaced-apart inner ends to form an electrical-insulation gap while still mechanically interconnecting them. These gauge-plate insulators are electrically insulating, so they include non-metallic (non-conducting) materials. Known gauge-plate insulators include a metallic core and a polyurethane insulating encasement. Other gauge-plate insulators have been made of a laminated SCOTCHPLY material, a high-strength fiber-reinforced phenolic material (Minnesota Mining & Manufacturing Company, Saint Paul, Minn.), and require the use of a separate insulating plug between the ends of the gauge-plate insulator to prevent material build-up that can cause an electrical short-circuit. While these known designs of gauge-plate insulators have proven operationally sufficient, they tend to be costly due to the high-performance materials required and/or their multi-piece constructions.
Accordingly, it can be seen that there exists a need for a more cost-effective yet still durable and reliable way to mechanically interconnect but electrically insulate parallel rails of railroad tracks from each other. It is to the provision of solutions to this and other problems that the present invention is primarily directed.